Debate: a more systematically defined FLEX nib classification (based on large vintage 14k flex nib samples and data)

[Aether]

It's obviously not the laws of physics that are different.  In my opinion what changes the snapback of a nib is either a property of the material itself (type and/or alloy mix) and/or the geometry of the nib.  There is no conflict of observations, just different observations for different nibs.  There would only be a conflict if supposedly identical nibs behaved differently. 

 

A Pilot FA nib does not return to original state (as in position of tines) as quickly as a Leonardt Principal dip pen.  The first is made of gold and the second of steel. Suggesting springier properties of the steel nib.   There are also vintage gold nibs that snapback more quickly than the FA nib, and so I must conclude that in this example there must be another difference such as the tempering of the gold.  

 

There is no mystery to any of this really.

[duckbillclinton]

1 hour ago, Aether said:

A Pilot FA nib does not return to original state (as in position of tines) as quickly as a Leonardt Principal dip pen.  The first is made of gold and the second of steel. Sugges

 

Very good observation!  As an owner of 2x 742 FA and 2x 743 FA myself, you are correct on the FA nib characteristics!

[A Smug Dill]

2 hours ago, dipper said:

Bend any nib tine (gently, within its elastic limit) with your thumbnail, and then let the tine slip off your thumbnail like plucking a guitar string. The speed at which the tine springs back to its natural at-rest position is faster than the eye can see.

 

Sorry, but that isn't making much sense to me.

 

When you elastically deform a straight metal strip by applying force of constant magnitude in a direction orthogonal to both the length and the width of the strip, the degree to which the strip bends is not independent of (elapsed) time. It may take, say, 0.5s for the strip to bend as far as it will (elastically) under that amount of force, and so at elapsed time of 0.1s the strip will not have bent as far as it will have at 0.2s, and then at 0.3s, and so on. Whether it's “faster than the eye can see” is irrelevant; we all know it isn't instantaneous for any such metal strip.

 

Once the curvature of the strip has stabilised under the continuous application of that amount of force, reduction of that force to nil (i.e. releasing the end of the metal strip) does not result in the strip returning to perfectly straight instantaneously, either. Furthermore, the time vs curvature graph, starting from the moment of removal of that bending force, need not be symmetrical with the earlier part of the graph up to the moment. The degree at which the latter part is asymmetrical with the former part is the measure of, or difference in, snapback performance.

 

Maybe it takes sophisticated instruments with lasers and sensors to be able to measure it meaningfully; but it doesn't mean the phenomenon isn't real, or that it cannot be sensed. If the average person cannot measure or express it, so what? So ‘we’ can't communicate it with each other in an objective manner, but we can still experience it, and furthermore, have indisputably different experiences with various metal objects that have different levels of snapback performance.

[duckbillclinton]

3 hours ago, dipper said:

That's the problem.

I am a physics geek.😎😎😎.

 

Bend any nib tine (gently, within its elastic limit) with your thumbnail, and then let the tine slip off your thumbnail like plucking a guitar string. The speed at which the tine springs back to its natural at-rest position is faster than the eye can see.

 

But...

... So there is a conflict of observations here.

 

I hope this is due to a problem of communication. If the laws of physics are really different for some pen users then us physics geeks are in deep trouble!

 

The actual answer is way deeper than you thought, and it's not trivial either.  That's why no one from physics or engineering related fields took it seriously.  Maybe it's just that I am into math and a weirdo, well, what I am going to present maybe is just some good laughs.

[txomsy]

Or maybe it is all a simplistic approach. When solving complex problems we humans tend to divide it into orthogonal components that can be measured independently so we can simplify the analysis.

 

If you take a spring, like that of a ballpoint pen, stretch it and leave it alone it returns to its starting shape quickly, maybe too quick to see. Yet we all have experienced BPs with different responsiveness. So, what can be wrong?

 

The most simple approach is to deny everything and say it does not make sense. But the fact is that on the BP the spring is not acting alone, it is there not by its inherent aesthetic contribution or play joy, but to counteract other pressures and that is what makes it more or less springy. Take Lennard-Jones equations. Not all springs are exactly equal.

 

On a nib the same happens: whatever you do on a fingernail is totally pointless, it is just an approximate measure of one of many orthogonal factors, some of which may not quite be so and demand PCA or CCA to understand in real life. So the fingernail shows you tine spread, when you press against a mostly protein, relatively flat and soft surface. Not practical snapback when writing.

 

When you write, the nib is pressed against a more or less rough cellulose (or maybe keratin (in vellum) surface that has been (more or less) polished, sliding over a fluid (ink) and touching the paper surface. When you pull and suddenly release a string (or a spring, or a nib) the reaction is free and fast, when against paper, it cannot for there is a resistance opposing it.

 

Now, what you do not see without resistance, becomes apparent: if you release pressure against air there is no opposition and the tines close in all cases too fast. When you do it against dry, rough paper, the tines may catch against fibres and go too slow or even not close. When you do against a resisting surface lubricated with ink, then resistance is not too high, but neither is it negligible. Here, the elastic tendency of tines to recover their original tight contact position must work against the resistance and counterbalance it. The strongest that tendency, the strongest that spring, the faster it will overcome the resistance.

 

By definition a writer, as a human, will work as a feedback device and to control line width will move in the limits of equilibrium, and release will not be against air but against the resistance of paper/ink, so the line continues to be drawn, and tine closing will depend as much on the interaction tines-lubricant(ink)-surface(paper) as on the release by the writer.

 

What that means is, you can either slow down writing so that the release is slow enough to allow even the dullest nib to return to its original shape and produce the desired line widths, or, if you release faster than the ability of the tines to overcome the resistance, the line will thin out too slowly to produce the desired shape.

 

Obviously one can adapt their hand to the recovery speed (against friction resistance) of a given nib. But then enters ink and paper: if you always go very slow, some inks will spread on some papers, specially on the thick strokes which will become thicker, spidery and difficult to control. That again is easy to control if you write faster so the ink laid down per unit of time/paper surface covered is reduced.

 

But that, in turn, means you need to write thick strokes fast, entry strokes faster (to get a square top) and exit strokes more slowly (to allow tines to recover), and then you cannot keep a constant rhythm. That is why writers pay so much attention to snapback. Not because it is uncontrollable, but because it makes it easier to write with a constant rhythm which eases in turn maintaining constant shapes and uniformity, which are essential to calligraphy (beautiful writing).

 

OTOH the faster the snapback, the faster one has to write, which is why beginners are advised to use less flexible dip nibs so they can write slower.

 

If you want to see it in action, try a dip pen nib on a rough paper and compare with an FP. I very, very seldomly get ink droplet spills with an FP, but you have to be careful when using a flexible dip pen nib (even a Zebra G) for it is very easy a tine will catch on a fiber, and as the nib is moved, release suddenly and spill out droplets of ink all around. Which is another reason why paper becomes so important on calligraphy. That is because of the interaction between springiness of the tines, length of the tines (and balance's law), and the movement over a non-uniform surface with ink (if you do it without  ink, you will not see it -no droplets- though you may feel it in the fingertips).

[Bo Bo Olson]

Sprung and or mushy....is slow snapback. Is that a given? Ie a line that remains too wide from some flex*, to the wish for no flex narrow line before the next swelling of flex.

The super thin line makes the swelling of some to much flex letter appear much steeper/quicker to expand, even if it in not overly wide.

* Those who can write are not into extreme flex.....slows down writing? Slows down fast snapback.

 

A fine poster had an article from Waterman in the '30's where they were aiming for a 3X tine spread with ease of tine spread A Waterman Pink....was only designed to go 3X????? spread.............oh, oh, oh, so it would appear we are all over stressing the nibs...

 

For those who can write....absolutely not me, could say in how much of what letter fast snapback is achieved or not.

 

As of yet none of them have appeared in this section of the tread...they; I've been told have no interest on how wide a letter is...so might have written this thread off, before to them the interesting part comes.

Could it be someone bold must go over to the Writer's section and ask for aid?  

 

Could be someone 'knows' one of those rare creatures; 'those who can write'. 

Or starts a thread there, 'what is fast snapback?'

It appears to me physics buckyballs keeps butting heads with fountain pen quantum mechanics.

 

 

[duckbillclinton]

I am still alive. LOL  Will write out the flex nib writing strength reduction explanation, and will try to demystify the so call snapback speed.  Meanwhile, I have been really busy with personal life, and are working with some online pen pals to perform some lab test on certain flex nib characteritics.  Hopefully this will help us to understand more on designing a proper modern day flex nib.

 

Will update in 3 weeks before the end of October.😁

[LordCactus]

I modded a jinhao nib to flex to 12mm max and 3mm with almost no pressure! Can we add another catogory "future flex" for 1cm+ of flex nibs?

 

 

[Bo Bo Olson]

Really got to have a pump on that nib to put out so much ink with that 'obscenely'  wide a tine spread.

I've never seen that much tine spread.

 

I find it a bit too much....but such wideness is new to me an who knows what I'll think with more examples.

[LordCactus]

2 hours ago, Bo Bo Olson said:

Really got to have a pump on that nib to put out so much ink with that 'obscenely'  wide a tine spread.

I've never seen that much tine spread.

 

I find it a bit too much....but such wideness is new to me an who knows what I'll think with more examples.

Here is anothet one!

[txomsy]

That looks like an interesting development.

 

Is that a trade secret, a projected patent or a shareable mod?

 

That looks to me like a rather extreme modification.

 

Personally, I tend to feel skeptical about its durability, but not knowing, I cannot say.

 

It looks like (at least) one tine has been slimmed down to ~1mm in all its length. That can only open so much by either potentially lasting too little (because of a huge strain in the metal at the junction with the other tine which would lead to plastic deformation and springing) or having a hinge with the other tine. In the last case, for that to then close would need either a spring or a suitably shaped over-nib construct that provides the force to bring it back (and might potentially act as an overfeed).

 

Even then, I doubt so much ink can flow  through those tines without an ink film forming, so maybe there is something else (an intermediate third tine or tube or a leaf) in between to help lay the ink?

 

The feed would also need to be modified to provide appropriate ink flow as @Bo Bo Olson points out. Jinhao feeds are known to be unable to cope with the needs of line variation sustainably with less demanding (e.g. the Zebra/Nikko G) flex nibs and apart from delivering large quantities of ink when full open it should be able to buffer the excess ink when writing thin lines..

 

Do not misconstrue me, no one says an FP nib cannot have a totally new, groundbreaking design. I'm just skeptical and curious.

[LordCactus]

48 minutes ago, txomsy said:

That looks like an interesting development.

 

Is that a trade secret, a projected patent or a shareable mod?

 

That looks to me like a rather extreme modification.

 

Personally, I tend to feel skeptical about its durability, but not knowing, I cannot say.

 

It looks like (at least) one tine has been slimmed down to ~1mm in all its length. That can only open so much by either potentially lasting too little (because of a huge strain in the metal at the junction with the other tine which would lead to plastic deformation and springing) or having a hinge with the other tine. In the last case, for that to then close would need either a spring or a suitably shaped over-nib construct that provides the force to bring it back (and might potentially act as an overfeed).

 

Even then, I doubt so much ink can flow  through those tines without an ink film forming, so maybe there is something else (an intermediate third tine or tube or a leaf) in between to help lay the ink?

 

The feed would also need to be modified to provide appropriate ink flow as @Bo Bo Olson points out. Jinhao feeds are known to be unable to cope with the needs of line variation sustainably with less demanding (e.g. the Zebra/Nikko G) flex nibs and apart from delivering large quantities of ink when full open it should be able to buffer the excess ink when writing thin lines..

 

Do not misconstrue me, no one says an FP nib cannot have a totally new, groundbreaking design. I'm just skeptical and curious.

The tines have not been thinned at all, I have cut out an arrowhead shape from the breather hole. I will keep testing and in a year or so I'll let you know if it has fatigued/sprung. It should be able to do 3mm flex easily and indefinitely

 

[LordCactus]

55 minutes ago, txomsy said:

That looks like an interesting development.

 

Is that a trade secret, a projected patent or a shareable mod?

 

That looks to me like a rather extreme modification.

 

Personally, I tend to feel skeptical about its durability, but not knowing, I cannot say.

 

It looks like (at least) one tine has been slimmed down to ~1mm in all its length. That can only open so much by either potentially lasting too little (because of a huge strain in the metal at the junction with the other tine which would lead to plastic deformation and springing) or having a hinge with the other tine. In the last case, for that to then close would need either a spring or a suitably shaped over-nib construct that provides the force to bring it back (and might potentially act as an overfeed).

 

Even then, I doubt so much ink can flow  through those tines without an ink film forming, so maybe there is something else (an intermediate third tine or tube or a leaf) in between to help lay the ink?

 

The feed would also need to be modified to provide appropriate ink flow as @Bo Bo Olson points out. Jinhao feeds are known to be unable to cope with the needs of line variation sustainably with less demanding (e.g. the Zebra/Nikko G) flex nibs and apart from delivering large quantities of ink when full open it should be able to buffer the excess ink when writing thin lines..

 

Do not misconstrue me, no one says an FP nib cannot have a totally new, groundbreaking design. I'm just skeptical and curious.

I am using a flexible feed and flexible overfeed I made from an eraser. I call it the "Sandwich Feed"

[Bo Bo Olson]

I have three Wet Noodles and one Weak Kneed Wet noodle, none would lay such a wet line.

 

 I'm not sure if even my dip pen  Hunt 99-100-101 (do got to use them sometime) which are by far my most flexible nibs would lay such a wide line....and What ink was Used????

 

Wet noodles lay in the first third of dip pens flex rates, and my Weak Kneed Wet Noodle is about middle of the dip pen flex rates.

[LordCactus]

26 minutes ago, Bo Bo Olson said:

I have three Wet Noodles and one Weak Kneed Wet noodle, none would lay such a wet line.

 

 I'm not sure if even my dip pen  Hunt 99-100-101 (do got to use them sometime) which are by far my most flexible nibs would lay such a wide line....and What ink was Used????

 

Wet noodles lay in the first third of dip pens flex rates, and my Weak Kneed Wet Noodle is about middle of the dip pen flex rates.

I ran out of inks so I mixed what I had left and added water!

[Bo Bo Olson]

1 hour ago, LordCactus said:

and added water!

Ah, Ha....a trick I've read once a long time ago, vaguely.

 

I do have enough ink wells, just got to find a notable ink and water it a bit, to prevent extreme tine spreed rail roading...it looks like.

[LordCactus]

29 minutes ago, Bo Bo Olson said:

Ah, Ha....a trick I've read once a long time ago, vaguely.

 

I do have enough ink wells, just got to find a notable ink and water it a bit, to prevent extreme tine spreed rail roading...it looks like.

In case you are interested, I just made one that swells to 1.5cm+ max. 

 

[Bo Bo Olson]

JC on a crutch!!!

Woooff!!!

[LordCactus]

Made a chart

[kazoolaw]

Coming late to the topic:  are there objective standards for the speed of "snap back" and for the amount of pressure exerted to produce a certain line width?